Agricultural small plot field research trials are designed to measure treatment effects on the plots. Plot treatment use common chemical application methods including, for example, foliar, soil, drench, in-furrow, and seed treatment. When the treatment is a chemical, like a pesticide (such as herbicide, insecticide, fungicide, nematicide, etc.) the measurement is usually taken to detect evidence of deleterious plant effects. Although in some cases, the chemical enhances the plant and the measurement detects an increased plant quality.
These measurements require extensive, and time consuming visual ratings of field plots for phytotoxicity or other plant injury such as stunted growth, poor stands or similar measurements. These ratings are then used in selecting plants with tolerance to a pesticide of interest or testing for screening pesticidal usefulness on plants. These field ratings are very time consuming and subjective even when persons with highly specialized skill sets are employed. Each plot must be rated for multiple components of herbicide injury, and each component is visually rated on a 0 to 100 scale. There is variability in ratings due to the interval of time required to rate numerous plots, and due to testing individuals' skill level and individual biases. If plot plant quality is compromised due to environmental conditions unrelated to the treatment, such as hail, disease, wind, then the plot results are not useful because the intended treatment cannot be accurately measured. Existing procedures require evaluation of plot phytotoxicity approximately four to thirty days after applications. Plants are counted or visually scored for plant injury and plant death. Plots not meeting minimum quality standards are noted for exclusion from further analysis. These ratings will range from early vegetative to reproductive growth stages. Multiple ratings allow for a more detailed understanding of the plant response to pesticide injury but existing manual procedures are costly, labor intensive and not always precise.